[Author: agrieve]
[Author: agrieve]

-Forward SYMROOT and friends in BuildUsingXCodeBuild.sh. They appear to be required in order for projects that #import generated files from sub-projects.

R=thomasvl
APPROVED=thomasvl
DELTA=6  (5 added, 0 deleted, 1 changed)

git-svn-id: 741c308154f1e22deafec9707230e8b816ec4ca6@532 7dc7ac4e-7543-0410-b95c-c1676fc8e2a3

chao787/GTM-mirror,chao787/GTM-mirror,chao787/GTM-mirror